#include<stdio.h>
#include<unistd.h>
#include<string.h>

int main()
{
  printf("hello printf!\n"); //stdout
  perror("perror!");       //strderr

  fprintf(stdout,"stdout: hello fprintf\n"); //1
  fprintf(stderr,"stderr: hello fprintf\n"); //2
  //C语言函数
  //printf("hello printf\n");
  //fprintf(stdout,"hello fprintf\n");

  ////system
  //const char* msg = "hello write\n";
  //write(1,msg,strlen(msg));

  //fork();
  return 0;
}
